1. Field of the Invention
The present invention relates to a photographic camera provided with a focal plane shutter having a plurality of vertically-movable shutter blades.
2. Description of the Prior Art
As shown in FIGS. 1A and 1B, a photographic camera such as a single lens reflex camera 10 provided with a focal plane shutter 12 having a plurality of vertically-movable shutter blades at the rear portion of the camera body 14 is known in the art. The focal plane shutter 12 of this type comprises a leading-shutter blade 16 which consists of a plurality of thin metal plates 16a, 16b and 16c and a trailing-shutter blade 18 which also consists of a plurality of thin metal plates 18a, 18b and 18c similar to those of the leading-shutter blades 16. The leading-shutter blade 16 is movably mounted on the first shutter base plate 20 having an exposure aperture 20a so that the leading-shutter blade 16 can move between its closing position where it covers the exposure aperture 20a and its opening position where it opens the exposure aperture 20a. Similarly, the trailing-shutter blade 18 is movably mounted on the second shutter base plate 22 having an exposure aperture 22a aligned with the exposure aperture 20a so that the trailing-shutter blade 18 can move between its closing position where it covers the exposure aperture 22a and its opening position where it opens the exposure aperture 22a. Between the leading and the trailing-shutter blades 16 and 18, there is provided a partition plate 24 having an exposure aperture 24a aligned with the apertures 20a and 22a. In FIG. 1A, both of the leading and the trailing-shutter blades 16 and 18 are shown schematically in somewhat exaggerated manner with their drive mechanisms removed, in order to avoid the complexity of the drawing and to indicate only the existing positions of the shutter blades 16 and 18 in the shutter cocked condition. While the detail arrangement of the shutter 12 is not shown in FIG. 1A for the abovementioned reasons, the detail construction of such focal plane shutter having a plurality of vertically-movable shutter blades as shown in FIG. 1A is disclosed in detail in my co-pending U.S. patent application Ser. No. 501,617 filed on Aug. 29, 1974.
In the shutter rest condition, both of the leading and the trailing-shutter blades 16 and 18 are positioned in their closing positions. When the shutter 12 is charged or cocked interlockingly with the film take-up operation, the trailing-shutter blade 18 is moved in the transverse direction across the feed direction of a film 25 i.e. in the vertical direction and finally positioned beneath the apertures 20a, 24a and 22a, namely in the opening position, with its thin plates 18a, 18b and 18c collapsed each other.
On the other hand, in the camera body 14, mirror operating mechanism 26 is provided for operating a movably supported reflex mirror 28 which constitutes a part of a view finder reflex system generally indicated by the reference 30 together with a pentagonal prism 32 and a view finder lens 34. The reflex mirror 28 and the mirror operating mechanism 26 are in the position shown in FIG. 1A after the shutter 12 has been cocked.
When a shutter release button 36, shown schematically by the dotted line in FIG. 1A, is depressed, a lock lever 38 is turned in the counterclockwise direction and disengaged from a pin 40 fixed to an actuating lever 42 which is rotatably supported by a shaft 43. Accordingly, the actuating lever 42 is moved in the counterclockwise direction by a spring 44 provided between the one end of the actuating lever 42 and set lever 45 which is also rotatably supported by the shaft 43. Since the other end of the actuating lever 42 is furcated and a pin 46 fixed to a bent portion 48a of a pivotally movable mirror support member 48 is positioned between the furcation, the mirror 28 is moved in the clockwise direction together with the mirror support member 48 in accordance with the counterclockwise movement of the actuating lever 42 and finally positioned in the position shown in phantom in FIG. 1A. In response to the mirror 28 being positioned in the phantom position, the leading-shutter blade 16 is rapidly moved upwardly by a shutter drive mechanism not shown in FIG. 1A and is positioned above the apertures 20a, 24a and 22a, namely in the opening position, with its thin plates 16a, 16b and 16c collapsed each other. In this way, the exposure for the film (not shown) is begun. Subsequent to the beginning of the exposure, the trailing-shutter blade 18 is released from its opening position by the well-known timing mechanism (not shown) after a certain time delay, moved rapidly and upwardly by the shutter drive mechanism and positioned in its closing position for terminating the exposure. The leading-shutter blade 16 returns to its closing position from its opening position in response to the trailing-shutter blade 18 being brought into its closing position. At the same time, in response to the leading-shutter blade 16 returning to its closing position, a lock lever 50 is moved in the counterclockwise direction by a suitable link mechanism (not shown) for releasing the set lever 45 from the position shown in FIG. 1A. Accordingly, the set lever 45 is moved in the clockwise direction, together with the actuating lever 42, by a spring 52 and the mirror 28 returns to the position shown by the solid line in FIG. 1A.
In this way, the whole mechanisms of the camera 10 will be in the rest condition. From this rest condition, if the shutter 12 is charged interlockingly with the film take-up operation the trailing-shutter blade 18 is positioned in its opening position, and, simultaneously, the set lever 45 is moved counterclockwise direction against the spring 52 by means of the rightward movement of the lever 54 which is moved interlockingly with the film take-up operation until the set lever 45 is locked by the rock lever 50. Therefore, the stand-by condition for photographing is obtained.
In such conventional camera 10 as described heretofore, a sufficient space S is provided at the upper portion of the first shutter base plate 20 and the partition plate 24 for the purpose of completely hiding the collapsed thin plates 16a, 16b and 16c of the leading-shutter blade 16 and the optical path from the pentagonal prism 32 to the view finder lens 34 in the view finder optical system 30 is positioned above the first shutter base plate 20 so as not to be obstructed by the thin plates 16a, 16b and 16c of the leading-shutter blade 16. As a result of these arrangements described above, the conventional photographic camera provided with the focal plane shutter having a plurality of vertically-movable shutter blades has a drawback in which the height of the camera as a whole can not help being higher than that of the camera provided with a focal plane shutter having a pair of horizontally-movable curtains, that is, the volume of the camera which is originally required to be compact is much larger than that of the above-mentioned camera having the horizontally-movable curtain type shutter.